using System;
using System.Collections.Specialized;
using EnvDTE;
using Microsoft.Practices.RecipeFramework.Library;
using VSSDKAssist.Assets.ValueProviders.Base;

namespace VSSDKAssist.Assets.ValueProviders.VisualStudio
{
	/// <summary>
	/// Value provider for a project item by name
	/// </summary>
	public class ProjectItemByNameValueProvider : ValueProviderBase
	{
		#region Constants
		private const string ItemName = "ItemName";
		private const string ProjectArgument = "ProjectArgument";
		#endregion

		#region Fields
		private string itemName;
		private string projectArgument;
		#endregion

		/// <summary>
		/// Contains code that will be called before actions are executed.
		/// </summary>
		/// <param name="currentValue">An <see cref="T:System.Object"/> that contains the current value of the argument.</param>
		/// <param name="newValue">When this method returns, contains an <see cref="T:System.Object"/> that contains
		/// the new value of the argument, if the returned value
		/// of the method is <see langword="true"/>. Otherwise, it is ignored.</param>
		/// <returns>
		/// 	<see langword="true"/> if the argument value should be replaced with
		/// the value in <paramref name="newValue"/>; otherwise, <see langword="false"/>.
		/// </returns>
		/// <remarks>By default, always returns <see langword="false"/>, unless overridden by a derived class.</remarks>
		[System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Design", "CA1031:DoNotCatchGeneralExceptionTypes")]
		public override bool OnBeforeActions(object currentValue, out object newValue)
		{
			newValue = null;

			if((currentValue == null) && (this.ExecutionStage != Stage.OnBeginRecipe))
			{
				Project project = DictionaryService.GetValue(projectArgument) as Project;

				if(project != null)
				{
					try
					{
						newValue = DteHelper.FindItemByName(project.ProjectItems, itemName, true);
					}
					catch
					{
						//With Web projects without any subfolder this method throws an exception
						newValue = DteHelper.FindItemByName(project.ProjectItems, itemName, false);
					}

					if(newValue != null)
					{
						return true;
					}
				}
			}

			return false;
		}

		/// <summary>
		/// Called when [configure].
		/// </summary>
		/// <param name="attributes">The attributes.</param>
		protected override void OnConfigure(StringDictionary attributes)
		{
			if(attributes == null)
				throw new ArgumentNullException("attributes");

			if(attributes.ContainsKey(ItemName))
			{
				itemName = attributes[ItemName];
			}

			if(attributes.ContainsKey(ProjectArgument))
			{
				projectArgument = attributes[ProjectArgument];
			}
		}
	}
}